I have a Tyco on my breadboard. I've tried 3 variations of the circuit; Mr Huge's Tycobrahe schematic, the hand drawn one and the Dunlop Octavio. No matter how I combine the dozen different types of transistors I have I don't get such a nasty and thick sound.

I've had the GGG Tyco and the wedge Dunlop octavio. I've watched a bunch of YT videos of different clones and I'm starting to believe the guys who claim that there is nothing like an original Tycobrahe.

Howdy folks, first post here. This thread is pretty old with a good bit of "link rot", but from the surviving gut shots it seems Q1 is reversed from some of the common schematics floating around the web (GGG and Fuzz Central), with emitter connected to the 220r and 220k etc. The Jeorge Tripps-drawn schematic I have backs that up.

Can anyone confirm that the original Tycobrahe transistors are MPSA18, 2x 2N6519?

4ab3c1b wrote:Howdy folks, first post here. This thread is pretty old with a good bit of "link rot", but from the surviving gut shots it seems Q1 is reversed from some of the common schematics floating around the web (GGG and Fuzz Central), with emitter connected to the 220r and 220k etc. The Jeorge Tripps-drawn schematic I have backs that up.

Can anyone confirm that the original Tycobrahe transistors are MPSA18, 2x 2N6519?

Thanks!

I can confirm the q1 is MPSA18. I'm looking for pics of the others as we speak.

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I got the GGG kit the other day and have been collecting schematics along the way. Some observations...

1) With the exception of the early hand drawn and Dunlop schematics, all the others seem to be the same. Am I missing some glaring discrepancies?

2) The completed GGG kit left me underwhelmed so I started digging around and checking things.

- MPSA18's have a gain range of 500-1500hfe (according to current datasheets). I built the negative ground version which uses a 2N5087 and has a gain range of 250-900hfe. I did not measure mine yet.

- MPS6519's have a gain range of 250-500hfe (according to current datasheets). The GGG kit uses 2N4401's and they have a gain range of 100-300hfe.

3) I kept the 2N5087 because I didn't have anything else on hand but swapped the 2N4401's for 2N5088's and noticed an improvement. The fuzz portion sounds closer to what it should.

4) I had read that the diodes need to have low forward voltage ratings and some people posted that they got better octave results if the diodes were matched. I did swap out the Ge diodes GGG sent with some low forward voltage ones I had and got a stronger octave.

5) I have a Chicago Iron Octavia coming in tomorrow, I'll dissect and report.